The present disclosure relates, generally, to battery life testing of battery-powered audio system, and more particularly to a method which utilises an amplitude regulated audio signal for estimating and assessing the battery life of such products.
One of the challenges in measuring the playtime duration of battery-equipped audio products is that there is no particular test signal that has the appropriate characteristics of music regarding its dynamic behaviour. A signal like that would not only present an energy distribution, within the typical audible spectrum, similar to the one found in music but would also simulate its dynamics.
A conventional method for estimating the playtime duration of battery-equipped audio products employs a preprocessed white noise signal, shaped in frequency according to the average of the power spectral density of music, as test signal. Nevertheless, in time-domain, white noise exhibits a long-term constant envelope, such characteristic do not well represent the dynamic behaviour of music and that is why this conventional method may provide inaccurate results. This inaccuracy relies upon the fact that when music is played on battery-equipped audio systems, with a relatively high volume, compressors and/or limiters are internally engaged to adjust or limit the output level and consequently, the energy consumed from the battery decreases. However, a white noise signal containing the same amount of energy as the high-volume music signal mentioned before, will unlikely engage any compressor or limiter, which leads the system to consume more energy.
Therefore, heretofore unaddressed needs still exist in the art to address the aforementioned deficiencies and inadequacies.